The trial is expected to last until April. The defendants are all in custody.

Mr Lucas added: "The defendants, and others not before the court, used and abused the six complainants persistently over long periods of time, sometimes in groups, for their own sexual gratification and the sexual gratification of others. The depravity of what was done to the complainants was extreme." He told the jurors that the details of the case would make them uncomfortable.

Mr Lucas said the men "actively targeted vulnerable young girls from the ages of 11 or 12". Sometimes the abusers would come across them while they were playing truant or out drinking.

He added: "There is evidence that the men deliberately targeted children who were out of control. They also targeted children who had been sent to live in care homes for precisely that reason. Some of the girls had been sexually exploited by other men, before they encountered these defendants. Some girls already being abused by the group were tasked to find other girls for the group." He said the girls were chosen because they had troubled upbringings which made it less likely that anyone would have parental control over them or be looking for them.